[jitsi-dev] One Way Audio with ilbc / OK with G711


Hi guys,

we are currently working with Jitsi connected to a Cisco UCM 8.0.
Everything is working OK if i use G711u or G711a. If we enable ilbc we
get a interesting error:
Signalling wise everything seems to be going OK, we see both sides use
the (seemingly) correct SDP.
In the Jitsi Logs I actually see we are not sending any packets:
11:39:59.793 INFO:
impl.neomedia.MediaStreamImpl.printFlowStatistics().2257 rtpstat:call
stats for outgoing audio stream SSRC:16493548
rtpstat:bytes sent: 0
rtpstat:RTP sent: 0
rtpstat:remote reported min interarrival jitter : -1
rtpstat:remote reported max interarrival jitter : 0
rtpstat:local collisions: 0
rtpstat:remote collisions: 0
rtpstat:RTCP sent: 4
rtpstat:transmit failed: 0
So it does not look like a codec mismatch problem I think.

this is also confirmed via the packet capture. I'm not sure why this
is happening only with ilbc, maybe someone can help me out :slight_smile:
I have attached both the Packet captures for both calls as well as the
SIP-Communicator logs.
SIP Comm. version is 1.0-beta1-nightly.build.3364
many thanks

2011-03-29@11.41.31-logs.zip (42 KB)

ilbc_.cap (63.4 KB)


Hello Bernhard,

Thank you very much for the great report! I've been able to reproduce
the problem with two Jitsi instances with iptel.org accounts. Could I
please ask you to open an issue in our issue tracker at

Best regards,


The problem is that the iLBC encoder expects to receive an audio
buffer of 30 ms and it is just currently not going to happen with
PortAudio which gives 20 ms. I'll fix it.

I also see that there's copying of the audio data from byte[] to
short[] and then from short[] to byte[] which is not cool so I'll take
care of it as well.


On Tue, Mar 29, 2011 at 12:47 PM, Bernhard Albler <bernhard.albler@gmail.com> wrote:

In the Jitsi Logs I actually see we are not sending any packets:


Hi Lyubomir,

sorry for answering so late, I was travelling. Many many thanks for your
analysis. Should I still open ticket ? Also can I help in any way?



Could you please test r8496? Thanks a million.


On Thu, Apr 7, 2011 at 8:07 PM, Bernhard Albler <bernhard.albler@gmail.com> wrote:

Also can I help in any way?


Sure, I'll send you the results until monday.
many thanks for the very fast fix.